text: #include "complex.h"
  #define ONE Complex(1.0,0.0)
  
  extern fcomplex aa,bb,cc,z0,dz;
  
  void hypdrv(float s, float yy[], float dyyds[])
  {
  	fcomplex z,y[3],dyds[3];
  
  	y[1]=Complex(yy[1],yy[2]);
  	y[2]=Complex(yy[3],yy[4]);
  	z=Cadd(z0,RCmul(s,dz));
  	dyds[1]=Cmul(y[2],dz);
  	dyds[2]=Cmul(Csub(Cmul(Cmul(aa,bb),y[1]),Cmul(Csub(cc,
  		Cmul(Cadd(Cadd(aa,bb),ONE),z)),y[2])),
  		Cdiv(dz,Cmul(z,Csub(ONE,z))));
  	dyyds[1]=dyds[1].r;
  	dyyds[2]=dyds[1].i;
  	dyyds[3]=dyds[2].r;
  	dyyds[4]=dyds[2].i;
  }
  #undef ONE
  /* (C) Copr. 1986-92 Numerical Recipes Software 7&X*. */
  